routine chem urinalysis and A&P Flashcards
hematuria
trauma to kidney
hemoglobinuria
presence of free hemoglobin in urine
interferences for blood
false negative: ascorbic acid
false positive: oxidants like bleach
acidic urine
prevents formation of alkaline kidney stones
inhibits development of UTIS
alkaline urine
prevents the precipitation and enhances the excretion of drugs
prevents the formation of acidic kidney stones
what are the 2 sources of protein in urine
plasma and RTE cells
protein interferences
false negative: presence of proteins that are not albumin
false positive: highly alkaline urines due to improper storage
clinical significance for nitrite
rapid screening for UTI
also can detect initial bladder infection (cystitis)
nitrite interferences
false negative: infection caused by pathogen that doesn’t reduce nitrate, ascorbic acid, insufficient incubation, absence of nitrate
false positive: contaminated specimen that has been sitting at room temp
reagent strip automation:
reflectance photometry
amount of reflected light indicate colour intensity
quantitative result
reagent strip QC for internal QC
performed daily & when new bottle is opened
reagent strip QC for external QC
proficiency survey
glucosuria is caused by?
hyperglycemia
what level of glucose is detected
2.2mmol/L
glucose interferences
false negative: ascorbic acid, improper storage
false positive: oxidizing agents like bleach
bilirubin
yellowish substance made during the bodies process of breaking down RBCs and helps diagnose liver disease
does normal urine contain bilirubin?
no
bilirubin interferences
false negative: ascorbic acids, nitrites, and improper storage
false positive: medications that induce colour in urine
bilirubin medications
phenazopyridine (UTIs)
indican
lodine (arthritis)
urobilinogen
only a small amount in normal urine
99% is eliminated in the feces (what gives it its colour)
urobilinogen interferences
false negative: nitrites, formalin, urine not at room temp or fresh
false positive: some drugs and atypical coloured urines
urobilinigen > oxidized > urobilin (yellow) =?
doesn’t react to test
conjugated bilirubin> oxidized > biliverdin (green) =?
does not react in tests
conjugated bilirubin >hydrolyzed > unconjugated bilirubin =?
insoluble and less reactive
ketones in urine is an indication that
the body is using fats rather than carbohydrates for energy
what are the 3 ketone bodies
acetone 2%
acetoacetic acid 20%
b-hydroxybutyric acid 78%
ketonuria
elevated levels of ketone bodies in blood that results in their excretion into the urine
ketosis or ketoacidosis
diabetes mellitus
decreased carbohydrates supply
diabetes mellitus
body unable to use carbohydrates as an energy source uses fat stores instead of
decreased carbohydrates supply means what happens
starvation, fever, prolonged exercise and dietary imbalance
ketone interferences
false negative: improper storage
false positive: pigmented urine, compounds containing free sulfhydral groups
sulfhydral groups
phthalein compounds (laxatives)
levodopa (used to treat parkinson’s)
low SG for ketones means
dilute
over hydration
high SG for ketones
concentrated
dehydration
leukocytes
not designed to measure concentration
done by microscopic exam
advantage of chemical testing of leukocytes
detects WBCs that may have been lysed
60% of WBCs lyse within 2 hours of urine collection
what is the most common granulocyte
neutrophils
interferences for leukocytes
false negative: lots of glucose, high urine SG, lymphocytes present (not neutrophils)
false positive: contamination with vaginal discharge, contaminating oxidants
High SG if red cells present they may be?
crenated
low SG if white cells present they may be?
glittery
alkaline pH
some bacteria multiple rapidly at alkaline pH
if glucose is positive it means
the acidic glucose containing urine of patients with diabetes provide an ideal environment for yeast to grow
kidneys
paired organs about the size of a fist
ureters
carry urine from kidney to bladder via peristaltic action
urinary bladder
deflated when empty (pear shape)
urinary bladder how do we pee
the external sphincter muscle at the base of the bladder relaxes, this muscle is under cerebral control (when to perform and brain controls when not too)
urethra
transports urine from bladder out of the body
kidney anatomy (process)
blood is carried into each kidney via rena arteries
blood that has circulated through kidneys is collected by renal veins
renal veins empty into inferior vena cava and eventually back to the heart
the outer granular area of kidney is called
cortex
the inner striated area of the kidney is called what
medulla
medulla is arranged into *** and the tip is called the **
pyramids, papilla
lobe of the kidney is a ** and the **
pyramid and cortical cap
central area of the kidney is ** and it is collecting ** called the ***
hollow, basin, renal pelvis
as urine is produced it will flow from the:
papilla to minor calyx to major calyx to renal pelvis to ureter
kidney function of excretory
removes wastes from the blood in the form or urine
kidney function of regulatory
retention of nutrients (glucose, proteins, h2o)
acid base balance (pH maintenance)
electrolyte water balance (h2o follows Na)
kidney functions of endocrine
synthesis of hormones (adrenal glands) such as:
erythropoietin
renin
vitamin D
in the endocrine system during kidney function what does erythropoietin mean
production of RBCs
in the endocrine system during kidney function what does renin mean
controls blood pressure
excretory and regulatory functions are carried out by 3 processes that occur in the nephrons:
- glomerular filtration
- tubular reabsorption (PCT)
- tubular secretion (DCT)
where does the tubular reabsorption happen
proximal convoluted tubule (PCT)
where does tubular secretion happen?
distal convoluted tubule (DCT)
nephron does what
filters blood
where is the nephron located
in each pyramid and span both the cortex and the medulla areas
blood circulation:
blood ENTERS the glomerulus through the AFFERENT arteriole
blood LEAVES through the EFFERENT arteriole
blood delivery begins urine formation
glomerular filtration is
substances are filtered from blood plasma, though the glomerular membrane into the bowman’s capsule
what gets filtered in the glomerular and what doesn’t
large molecules like WBC, RBC, stay in plasma
but small substances get filtered like (electrolytes, glucose, uric acid)
rate of filtrate formation is called
glomerular filtration rate (GFR)
now called creatinine level
what is tubular reabsorption
the process by which water and dissolved substances in the urine filtrate move from the renal tubules back into the blood of the peri tubular capillaries
where does most of the process of tubular reabsorption occur
occurs in the PCT
tubular secretion is and occurs mainly in
the movement of substances out of the blood into the filtrate and occurs mainly in the DCT
renal threshold
minimal concentration of a substance in the blood where it appears in urine
glucose concentration in blood is
10mmol/L
threshold substance
appears in urine only after exceeding a certain concentration in the blood
threshold substances include
amino acids
glucose
positive ions
normal blood glucose is
5.5mmol/L
renal threshold of glucose is ** mmol/L in blood not urine
10mmol/L
urea and negative ions are not threshold substances? t or f
true bc they are passively reabsorbed
Na+ and K+ are ** ions that are ** reabsorbed, but not threshold substances because ***
positive, actively, they are secreted in the DCT and appear in urine even when blood concentration are low
urinary tract brush biopsy
used to obtain a renal tissue specimen
bacteriuria
presence of bacteria in urine
oliguria
elimination of small amount of urine
pyuria
presence of pus in the urine
urinary stasis
stoppage of urine flow
calculi
kidney stones
dysuria
painful urination
sign of UTI
uremia and azotemia
condition in which substances that are normally excreted in urine accumulate in the blood
(urea or creatinine)
enuresis or incontinence
inability to control peeing
cystoscopy
inspection of the urinary bladder by means of an instrument called a cystoscope
renal biopsy
diagnostic test for evaluating certain types and stages of kidney diseases
nephritis
inflammation of the kidney tissue
pyelitis
inflammation of the renal pelvis and calyces
(early stage of pyelonephritis)
ren/o or nephr/o
kidney
glomerul/o
glomerulus
pyel/o
renal pelvis
cali/o or calic/o
calyx
ur/o or urin/o
urine or urinary tract
ureter/o
ureter
cyst/o vesic/o
urinary bladder
urethr/o
urethra
SG means
specific gravity
GFR means
glomerular filtration rate
reflectance photometry
based on the principle that when light strikes a matte surface, like a dipstick some of the light is absorbed and the remainder is reflected
reagent strip QC is performed…
daily or when a new bottle is opened
glucosuria
presence of glucose in urine
glycosuria
presence of reducing sugars in urine, such as glucose, lactose, etc.
decreased carbohydrate supply:
starvation
dietary imbalance
prolonged exercise
in cases where fats are the main source of energy rather than carbohydrates, there are excessive amounts of…
acetoacetic acid produced
in normal urine how many RBCs should be seen
no more than 2-5 HPF
hemoglobin
iron/oxygen binding protein found in RBCs
myoglobin
iron/oxygen binding protein found in muscle tissue
a pH of 9 indicates the urine specimen is ** and has ** and what should be done
not fresh and has a lot of bacteria in it.
a new specimen should be collected
overload proteinuria
overflow of filtered, low molecular mass proteins
glomerular proteinuria
increased glomerular permeability to plasma proteins
tubular proteinuria
defective tubular reabsorption of protein from the filtrate
post renal proteinuria
inflammation of the lower urinary tract
what is the average urine volume excreted by an adult in one day
1500mL
what analyte occasionally found in urine can give a false high SG result
protein
what is a good indication of out of control diabetes mellitus?
glucosuria and ketonuria
what protein is the commercial reagent dipstick for?
albumin
what protein do RTE cells exude
uromodulin (tamm horsfall)
what is the normal renal threshold for glucose?
10 mmol/L
what can cause a significant pyuria without bacteriuria
UTI caused by a virus
what hormone is being tested for using a urine pregnancy test kit
human chorionic gonadotropin
what is the nitrate test on the dipstick a rapid screening test for?
UTI
which enzyme activity is being measured on the leukocyte test strip on the dipstick?
granulocytic esterase
glomerular filtration moves the filtrate through the glomerular membrane into which part of the nephron?
bowman’s capsule
the renal threshold of glucose is approximately?
10mmol/L
the substance not reabsorbed by the kidneys remain in the tubules and become?
urine
the outer granular area of the kidney is known as the ?
cortex
oliguria
the elimination of small amounts of urine
kidneys 3 main functions
excretory, regulatory and endocrine
which 2 functions occur in the nephrons
excretory and regulatory
what are the 3 processes that occur in the nephrons
tubular reabsorption, tubular secretion, and glomerular filtration
urine formation
mixture of 95% water and 5% dissolved substances
++ - +++ on reagent strip or no RBCs found in the microscope what’s the interpretation?
hemoglobinuria, myoglobinuria
negative on reagent strip and 10-20 RBCs on microscope what’s the interpretation?
false negative due to ascorbic acid
negative on reagent strip and 0-5 RBCs on microscope what’s the interpretation?
normal urine
not enough RBCs to give positive reaction
++ - +++ on reagent strip or not many WBCs found in the microscope what’s the interpretation?
false positive due to vaginal discharge and contaminating oxidants
negative on reagent strip or >5-10 WBCs found in the microscope what’s the interpretation?
false negative due to high urine SG
negative on reagent strip or 0-5 WBCs found in the microscope what’s the interpretation?
normal urine not enough WBCs to give a positive reaction
